Set up backend CI/CD

[irithsharma]

Points: 3

TODOs:

• [x] Add test stage
  • [x] Run unit tests
  • [x] Run integration tests
• [x] Add build stage
• [x] Add deploy stage
• [x] Validate that pipeline works as expected

Description: Implement initial pipeline to build backend artifact, run tests, and deploy to cloud service.

Notes: n/a